Drifting valve



Nov. 1, I92 7.

wrmsss:

1,647,887 H. L. ROBERTS DRIFTING VALVE Filefl July 5, 1921 2 Sheets-Sheet 1 Z5 if T I H.L afiolaerizs INVENTOR ATTF) RN EY Nov. 1, 1927. 1,647,887

H. L. ROBERTS DRIFTING' VALVE Filed July 5. 1921 gsneets-sneet 2 JZZJYaZarZa;

Q INVENTOR ATTORNEY WITNESS:

Patented Nov. 1, 1927.

earsnr :onrnrrne VALVE.

Application filed July 5,

This invention relates to improvements in drifting valves for locomotives, the general object ofthe invention being to improve and simplify the construction and operation of the valve forming the subject matter of the patent granted to me on May 29, 1923, numbered1,4:57,272. I V

Another object of the invention is to provide an auxiliary steam supply for moving the valve into drifting position as soon as the throttle is closed wit-hmcans for renewing this supply when the throttle is open.

This invention also consists in certain other features of construction and in the combination and arrangement of the several parts, to be hereinafter fully described,

7 illustrated in the accompanylng drawings and specifically pointed out in the appended claim. i I

In describing my invention in detail, reference will be had to the accompanying drawings wherein like characters oenote like or corresponding parts throughout the several views, and in which 2 y Figure 1 is a diagrammatic view showing the application of my invention.

Figure 2' is asectional View through the valve chest which controls the flow of steam to and from the auxiliary supply tank.

Figure 3 is a sectional View through the drift valve and showing means torsupplying the tank with steam from the cylinder.

Figure 4 is a view similar to Figure 3 showing the parts in drifting position.

Figure 5 is an enlarged sectional view through the valve 26.

In these views 1 indicates thesteam dome ofthe locomotive boiler, and 2 the lubri'cator which is connected with the dome by the pipes 3, in one ofwhi'chis located the valve 4:. T he drifting valve is shown at 5, the pump at G, and 7 indicates the throttle lever. The drift valve consists of the casing Sand the pistons 9, 10, 11 and 12 whichareconnect-ed together by the rods 13. Piston12 is larger than theother pistons and works in an enlargement" 8 of the casing The other pistons are or the same diameters but piston 9 is double headed to provide the groove 9.

A pipe 1% connects the end of the chamber formed by the enlargement 8" with a steam 1921. Serial No. teaser chest of one or the cylinders or with the pipe leading to the steam chest so that when the throttle is open steam will flow into the chamher to hold the pistons in inoperative position, as sl'iown in Figure 3. A piping 15 connects the casing, adjacentpiston 11, with the exhaust. pump 6 and piping 15 leadsthe exhaust from the stolser tos'aid piping 15 so that the oil laden steamfrom the pump and stoker will 'flow into the casing and will exhaust through the outlet 16 when the drifting valve is in a position normally held when the throttle is open, said posit-ion being hereinafter referred to as normal position as against the position taken when the throttle is closed and the pistons moving, which is termed drifting position. A by-pass 17 connectsthe piping 15 with the exhaust so as to prevent the exhaust of the pump and stoke-r being entirely closed if the piston 11 should fail to pass over the port leading to pipe 15. The inlet end of this pipe 17 is so formed that the exhaust will flow through. the casing, unless prevented, as thispath will o'fi'er the least resistance. Piping 18 connects the casing with the coupling 19 which connects the pipes 3 together so that when steam is turned on to the lubricator some of the steam will pass to the drifting valve. Piping 20 connects the casing with the steam chest of the cylinders, the connection of this piping with the casing -8 being a forked one, as shown at 20. A pipe -21 connects the piping 15 with a point in the casing 8 which is in alignmentwith the groove 9 of piston when the valve parts are in normal position. A pipe 22 connects the space formed by the groove 9 with the exhaust 16 and a port 9 connects the space formed by the groove 9 with the space between the pistons 9 and 10 so that the steam flowing into the casing from pipe 18 can flow to exhaust through the port and pipe 22 when the valve parts are in inoperative posit-ion. This will prevent steam from being trapped in, the space between the pistons 9 and 10, when the parts are in inoperative positionywhich might interfere with the operation of the device by permitting the steam to condense in the device. Pipe 21 serves to introduce some of the oil FF-ICE.

'HUGH L, ROBERTS, OF ROANOKE, VIRGINIA.

laden steam from the pump and stoker into the casing to lubricate the heads of piston 9. A tank 23 is connected with the small end of easing 8 so that the steam in this tank will act to force the pistons into drifting position as soon as the throttle is closed. Figure 3 shows this tank as being connected directly with the casing by means of pipe 2% and to the cylinder of the engine by means of pipe 25, said pipe 25 having a check valve 26 therein for preventing the steam from returning to the cylinder when the throttle is closed. Figures 1 and 2 show the tank 23 as being connected witha valve chest 27, this chest being connected with the steam supply of the lubricator by piping 28 and with the small endof casing 8 by the piping 29. This valve chest is formed with a pair of chambers 30 and 31 which are each provided with a valve seat 32 for receiving the valves 34 and 35. These valves are held to the seat by the springs 36. The lower part of chamber 30 is connected with the upper part of chamber 31 by means of the passage 37 so that when valve is open the steam from the boiler flowing through pipe 28 will pass into the valve chest into chamber 30, through port 3'? into chamber 31 and through pipe 33 into the tank 23. As valve is closed no steam can pass into pipe 29 which leads to the drifting valve. lVhen valve 35 is opened and valve 3% closed, this steam will flow from the tank 23 past the valve 35 into pipe 29 and thus act upon the valve parts to move the same into drifting position. The.

valves 34 and 35 are controlled from the throttle lever 7 by means of the link 39 which is connected with the stem of the T lever 40 which is pivoted to a part of the valve chest 27. The arms 41 of this lever are arranged to engage the stems of valves 34: and 35 so as to open the valve 34 when the throttle lever is moved to open the throttle and to open valve 35 when the throttle lever is moved to closed position.

From the above it will be apparent that when the throttle is closed the accumulated steam in tank 23 acting against piston 9 will move the parts into drifting position with the exhaust from the pump and thestoker passing into the space between the pistons 10 and 11 so that this oil laden steam will pass into the cylinders of the engine to lubricate the same. The steam flowing through pipe 18 will also pass into the cylinders as piston 10 will straddle the fork 20 when the parts are in drifting position. This steam mixing with the oil laden steam will prevent explosions of the oil in the hot cylinders. The passage of this steam through the right hand part of the fork will create a suction in the left hand part so as to suck the oil laden steam into the cylinders so that the pump and stoker do not have to work against back pressure. As soon as the throttle is opened some of the steam flowing to the cylinders will pass through pipe 1%. into the large end of the casing 8 and this steam acting against the large piston 12 will return the parts to inoperative position. should occur in the cylinder when the throttle is closed this pressure will act against the piston 12 and move the parts to inoperative position and thus cut off the supply of oil and steam to the cylinders and permit the exhaust from the pump and stoker to pass to exhaust. The valve will not go to drifting position again until the throttle has been opened. the tank recharged and the throttle closed again. The pressure in the tank then will move the valve to drifting position.

By my invention the engine cylinders and the parts of the drift valve are oiled by the oil in the exhaust from the pump and stoker. The valve is absolutely automatic and requires but very little attention. It also acts to save fuel as it requires but little boiler steam on account of using the air pump and stoker exhaust.

In the construction shown in Figures 1 and 2 the tank 23 is connected with the steam supply when the throttle is open so that said tank is stored with steam and then when the throttle is closed the tank is connected with the drifting valve so that the steam therein will move the parts to drifting position.

It will be seen that when the pistons are in drifting position the tank 23 will exhaust through the pipe 22 so that the steam from this tank will not interfere with the return of the parts to inactive position when the throttle is again opened.

It is thought from the foregoing description that the advantages and novel features of my invention will be readily apparent.

I desire it to be understood that I may make changes in the construction and in the combination and arrangement of the several parts, provided that such changes fall within the scope of the appended claim.

hat I claim is In a locomotive, a drifting valve comprising a casing, an enlarged end on said Casing, a plurality of pistons movable in said casing, one of the pistons being of larger diameter than the others and movable in said enlarged end, an inlet at one side of the casing at a point adjacent the enlarged end, an outlet pipe opposite the inlet, and both outlet and inlet being arranged at one side of one of the pistons when in normal position, a bypass connecting the inlet and out let, one of said pistons having an annulargroove, a steam supply pipe having connection with the casing, at a point in alignment with the groove when the piston is in normal position, a second pipe leading from the casing in communication with the groove serving as an outlet, an additional pipe If an excess pressure communicating With the cylinder between and a pipe controlled by the throttle concertain of said pistons and having connecnected to the enlarged end of the casing so tion with the steam chest of the cylinders that steam admittedthrough this pipe will 1 of the engines, a pipe leading from the casing return the valve to normal position. I

to the luhricator, so that some of the oil- In testimony whereof I aflix my signature.

laden steam will pass into the valve, a tank, a. pipe connecting the casing and the tank, HUGH L. ROBERTS. 

